Hi there, ive been doing alot of research and im getting a headache so i thought i would post and hope some kind person would clear up my confusion.

The current size of the tyres on my 1993 GTO are 205 40 r17. Judging by what ive read this could be the wrong size, is this so? Ive read they should be something like 245 45 r17's. Thats a difference of 8.66% from what i have (i could be plodding down the motorway at 64mph). it would be great if someone knew the actual circumference they should be. Or even better, i want to buy 18's, what would be the best size (something like 235 40 r18?). I just want a size where the tyres dont cost a fortune because they are rare.

Also a slight point of concern, what are the chances that the speedo has been set up in some way for the tyres the car is currently on (eg when it was imported) so if i put the proper size on it will be all wrong.

sorry to babble on, hope someone can help.

Thanks in advance!

235/35/18 would be the ideal tyre size. This most i have seen the GTO's sit on 215or 225/50/16 , Turbo GTO's ive serviced in the shop were 235/45/17 frunts and 245/40/17 rear

use a gps to check your speedometer. you'll know right away if it's already been corrected for your current tires.

i have still got the orignal GTO wheels on my '95 jap imported GTO and they had 235/45R17 fitted. ive just bought TOYO T1R PROXES TOYO T1 R - 235/45R17 97Y XL for mine. found www.camskill.com was the cheapest place for them. hope this helps

I have Work 18 inch alloys and 245/40/18 tyres fitted, and 245 fits the width of the rim perfectly, something like 235 could be a bit narrow, 35 could make the ride interesting on UK roads, what is the rim width?

i could be wrong (highly likely! :) ) but i think i might have trouble getting hold of 235/35/18 at a decent price. my gto is 4wd so i dont think having different tyre sizes would be good for it. thanks for the input :)



I ill borrow a gps from work and check it. your right, i think its the only way to be sure. cheers mate.



This seems to make sense :) your size of 235/45r17 is almost an exact match to the circumference of the size i found (235/40 R18, Dia:645 mm, Cir:2026 mm, Difference from your size:0.3 %) suggested on other sites. thanks :)



Its the original mitsubishi 17 rims, i have no idea how wide but i think i need to change them and while im at it i'll just up them to 18's they are looking rather tired and i cant find a tyre at a decent price that will fit them. 245/40/18 is close to the size i found (235 40 r18). thanks

I assume i ill have to get quite wide rims to fit these tyre sizes then?

I think im noticing a trend, no one has tyres anywhere near the size i have, i have tiny tyres. oh the shame :o :blush-anim-cl: both front tyres curently have lovely big splits round them ready to peel apart and kill me :( so i need to get this sorted asap!

Well i was just imputing wut ive commonlly seen , and yes i was refering to AWD GTO's that had the 235 frunt and 245 rear combination , running it in this manner is not a conflict cause one is wider than teh other , many around here do it that way as i have on my VR-S. Being the differance between frunt and rear widness is the reason we drop half a series, 45 to 40 and weve neevr had any issues , also its PZero tyres so hmm iono.

the help is much appreciated :) i just want to keep it simple for myself :blush-anim-cl: although, im sure im making this far more complicated than i should. does anyone know, in the manual that i cannont read (japanese) does it state a standard size?

hey im running 225/50/r16s on my GTO and i dont think i would want to go any smaller
i quite like how the 16s are nice and light but the ones have sit 1mm or so from the brake calipers
the car shakes when braking under high speed or whilst using them over a long period of time
i suggest if you go for the smaller lighter mags/tyres for performance, but make sure the caliper has plenty of clearance

See my GTO swheel/tyre sizes were acurate LOL

haha yea nice one

id gladly got for some 245/40/18 or something but im already paying $200 NZD per tyre for the 16s!!

haha so no thanks

Came from the factory with 245/45/17

with the factory heavy mags as well!

just saying.

So to update the thread. I bought myself new alloys with tyres attached :) the tyres are 225 40 r18 which i hope should be near enough what thay should be. they were the size tyre attached to the alloy for sale so i wasnt going to bother with a few mm :)

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nice wheels! just be careful not to kerb them!

thanks :grin: im parking right in the middle of the road from now on tho! i think the chrome valve caps that came with them are going to be gone in about 5 seconds tho, kids steal/collect them :( do you think its ok to super glue them on cos they match so well. will post a pic when i get them on the car. some cleaning is required first tho!

Take those caps off and give them to the kids On my last car they actually corroded on and when I went to put air in my tire it was impossible. Good thing I needed new tires because it did not come off. Even after a few hours of persuasion.